Chrysoblog/src/routes/rss.xml/+server.ts

import { getPosts } from '$lib/posts';
import siteMetadata from '$content/metadata.json';
import type { Post } from '$lib/types'

export const prerender = true;

export async function GET() {
	const posts: Post[] = await getPosts();

	const headers = { 'Content-Type': 'application/xml' }

	const description = siteMetadata?.description
		? `<description>${siteMetadata?.description || ""}</description>`
		: "";
	const url = siteMetadata?.url || "";
	const urlXml = siteMetadata?.url ? `
			<link>${url}</link>
			<atom:link href="${url}/rss.xml" rel="self" type="application/rss+xml"/>
		` : "";
	const xml = `
		<rss xmlns:atom="http://www.w3.org/2005/Atom" version="2.0">
			<channel>
				<title>${siteMetadata.blogName}</title>
				${description}
				${urlXml}
				${posts
					.map(
						(post) => `
						<item>
							<title>${post.title}</title>
							<description>${post.description}</description>
							<link>${url}/post/${post.slug}</link>
							<guid isPermaLink="true">${url}/post/${post.slug}</guid>
							<pubDate>${new Date(post.date).toUTCString()}</pubDate>
						</item>
					`
					)
					.join('')}
			</channel>
		</rss>
	`.trim()

	return new Response(xml, { headers })
}